1. Field of the Invention
The present invention is related to a locking device, and more particularly to a locking device that is used to position telescopic handles of a luggage item.
2. Description of Related Art
A telescopic handle of a luggage item is shown in FIG. 6. The telescopic handle is composed of a pair of vertical bar assemblies each with an inner tube (81) retractably received in an outer tube (80) and a horizontal bar (83) to connect the vertical bar assemblies. A conventional locking device (90) for locating the inner tube (81) at a desired position in the outer tube (80) has a sliding block (91) with an arcuate surface (92) formed at a first side thereof. A flexible ring (93) is fixed in the inner tube (81) and pushed against the arcuate surface (92) of the sliding block (91) by a resilient member (96) provided therein and has a bowl portion (95) to engage with the arcuate surface (92). A finger (94) is formed on the flexible ring (93) and extends out an opening (811) of the inner tube (81) and an aligned one of a plurality of apertures (82) of the outer tube (80). A linkage (85) has a first end connected with the sliding block (91) and a second end connected with a lever (not numbered). The locking device is controlled by a button (84) provided in the horizontal bar (83) via the lever.
When the button (84) is pressed. the sliding block (91) is pulled upwards and the flexible ring (93) is compressed by the arcuate surface (92) to retract the finger (94) from the aperture (82) of the outer tube (80). Thus, a user can adjust the inner tube (81) to a desired position. Afterwards, the button (84) is released, and the finger (94) extends out another aperture (82) of the outer tube (80) at the desired position.
However, the conventional locking device has following shortcomings:
1. Because the engagement between the flexible ring (93) and the inner tube (81) is a xe2x80x9csingle-pointxe2x80x9d, there is a great of chance for the flexible ring (93) to move unsteadily and the structure strength of the locking device is weak.
2. The flexible ring (93) made of plastic material will lose elastic flexibility after a long term use.
3. The linkage (85) is made by injection molding and the cost of manufacturing the linkage""s mold is high.
Therefore, the invention provides a locking device for a telescopic handle to mitigate and/or obviate the aforementioned problems.
The main objective of the invention is to provide a locking device for a telescopic handle which has a stable structure.
Another objective of the invention is to provide a locking device for a telescopic handle which has a low manufacturing cost.
Another objective of the invention is to provide a locking device for a telescopic handle which can be assembled easily.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.